Actuator for door opening mechanism



Aug. 21, 1951 Y BURKE 2,564,750

ACTUATOR FOR DOOR OPENING MECHANISMS Filed March 5, 1949 3 Sheets-Sheet l INVENTOR.

Z6 iames FD. 60/742".

Aug. 21, 1951 J. P. BURKE 2,564,750

ACTUATOR FOR DOOR OPENING MECHANISMS Filed March 5, 1949 3 Sheets-Sheet 2 IN V EN TOR. Jame; 2. 50/3419.

Aug. 21, 1951 BURKE 2,564,750

ACTUATOR FOR DOOR OPENING MECHANISMS 3 Sheets-Sheet 5 Filed March 5, 1949 INVEN TOR. James 55 Eur/Pa.

Patented Aug. 21, 1951 UNITED STATES PATENT OFFICE ACTUATOR FOR DOOILOPE'NING MECHANISMS.

James P. Burke, Poland, Ohio, assignor; by direct and mesne assignments, of onei-h'alfztoilvlurray M. Fibus and one-half to'zJerome W. Marcus, both of Youngstown, Ohio Application March 5, 1949, SerialNo'. 79,897

1 Claim. 1

sionof a relatively simple and inexpensive actuator for dooropening mechanisms.

A still further object of the invention is the provision of an actuator for'door opening mechanisms which may be easily installed in present door openings.

A still further object of the invention is the provision of an actuator for door opening mechanisms which will operate to open the door when a person steps on the actuating mechanism and which will operate to prevent the door from opening when a person approaches the door from the opposite side.

A still further object of the invention is the provision of a simple, inexpensive and easily formed actuator for door opening mechanisms.

The actuator for door opening mechanisms disclosed herein comprises a simple and efiicient device for controlling an air piston and cylinder assembly which in turn applies motion to a door for openin and closing the same. The actuator disclosed herein is so formed that itmay be easily positioned in existing doorway constructions without remodeling the said constructions or altering the structures thereof and may be removed from the doorway without necessitating expensive floor repairs or replacements.

The device includes a simple mechanism for utilizing the weight of a person approaching the door to open an air valve and thereby actuate the door and is so formed that it will hold the door open until the person passes therethrough and moves off of the device. The actuator for door opening mechanisms also includesmechanism for rendering the device inoperative when the door is approached from the wrong side to eliminate the possibility of accident.

With the foregoing and other objects in view which will appear as the description proceeds, the invention resides in the combination and arrangement of parts and in the details of construction hereinafter described and claimed, it being understood that changes in the precise embodiment of the invention herein disclosed can be made within the scope of what is claimed without departing from the spirit of the invention.

2 The invention is illustrated in the accompany.- ing drawing; wherein- Figure 1 is a perspective view with parts broken away of'the actuator for door opening mechanismsapplied to a hinged door in a doorway equipped with an air cylinder opening mechanism.

Figure 2 is a top plan view with partsbroken away of the actuator for door opening mechanisms.

Figure 3 is a horizontal section on linei-3--3 of Figure 2. g I

Figure 4 isan enlarged perspective detail'iof a portion ofthe mechanism shown in'Figurei 1.

Figure 5 is an enlarged perspective detail of a-portion of the mechanism shown inFig-ure 21 Figure 6 is a horizontal section taken online 6-6 of Figure 5.

By referring to the drawings and FigureJ-I'in particular it-wili' be seen that a door opening mechanism as defined by a frame lll'is' illustrated-and a door II is hinged therein for openinginwardly with respect to the frame I0; away from thepoint of view in Figure 1. The door II is hinged at the left edge, as viewed in Figure l, and thedoor frame Ill' supports a housing I2 enclosin an air piston and cylinder assembly l3 which is operatively connected by'suitable crank arms I 4 with an arm l5 secured bymeans of a plate 16 to the door I I. The air cylinder and piston assembly i3 is connected with asource ofcompressed air by means of a pipe l'l an'dthe source of compressed air is controlled by'avalire l8 cut into the pipe 51' and also locatedin the housing i2. .A lever I9 is pivoted as at 20*in'pro'ximityto an operating plunger 2| of the air valve ls which is'arranged so that when the plunger z'l is moved upwardly, as seen in Figure 1 of'tl'ie drawings, the air valve is opened and the air-piston and cylinder assembly energized. A flexible-cable- 22 is connected as at 23' to the pivot leverl9 and enclosed in a guiding'an'd protecting tube 24 which is preferably located within'the space defined by the door frame In.

The'tube 24 enclosing the flexible cable" 22- extends downwardly through the door frame t0 and outwardly beneath the door II where it is enclosed ina thin tread plate assembly which replaces the-usual sill of the doorway opening and which extends outwardly away from the door on both sidesthereof. The tread plate assembly includes a bottom plate 25, an entrance tread'plate 26 and exit tread plate 2?. The entrancetread plate is hinged as'at 28 to one of the' outermost ends -i of the bottom plateeziaand its inner end is supported on springs 29, in elevated relation to the tread plate 25. The exit tread plate 21 is hinged at its outermost edge by means of hinges 30 to the outermost opposite edge of the bottom plate 25 and is also supported in elevated relation to the bottom plate by springs 3| located underneath its innermost edge. The springs 29 and 3| are intended to normally support the tread plates 26 and 21 in elevated relation to the bottom plate 25 and to permit the tread plates 26 and 21 to be depressed at such time as a person steps thereon.

In order that the movement of the tread plates 26 and 21 may be utilized to actuate the valve l8, heretofore described, the tube 24 enclosin the flexible cable 22 is run beneath the bottom plate 25 to a point centrally with respect to the edges thereof and the flexible cable 22 connected to the vertical end of an L-shaped lever 32 which is pivoted between the arms of a bifurcated bracket 33 by a pivot pin 34 as best shown in Figure 4 of the drawings. The bifurcated bracket 33 is secured to the bottom of the bottom pan 25 and located in a depression formed in the floor over which the bottom plate 25 is positioned (see Figures 1, 3, 4 and of the drawings) An opening 35 is formed in the bottom plate 25 and a "vertically positioned rod 36 is positioned therein with its lower end resting on the horizontal portion of the L-shaped lever 32, it being observed that the rod 36 passes between the arms of the bifurcated bracket 33. The upper end of the rod 36 is secured to the tread plate 26 as indicated by the numeral 31 so that the rod 36 moves vertically when the tread plate 26 moves.

It will thus be seen that when the entrance tread plate 26 is stepped upon, as by a person approaching the door II, the coil springs 23 are compressed and the tread plate 26' moves downwardly, the movement being imparted to the vertically positioned rod 36 which in turn moves the L-shaped lever 32 and imparts movement to the flexible cable 22. This movement is in turn transmitted by the flexible cable 22 to the lever I9 which moves the plunger 2| of the air valve "I8 and admits air to the air piston and cylinder thereby causing the door I to be opened.

In order that the door I I may remain open until the person actuating the mechanism has time to walk through the doorway defined by the door -frame I0 and out of the way of the door means is provided for locking the entrance tread plate 26 in'depressed position so as to hold the :air valve I8 open and such means comprises a series of levers interconnecting the entrance tread plate 26 with the exit tread plate 21 as best shown in- Figures 2, 3, 5, and 6 of the drawings.

-By referring thereto it will be seen that at such time as the tread plate 26 is depressed, a depend- .ing bracket 38 secured thereto by fasteners 39 and movably positioned through a slot 40 in the bottom plate 25, engages and moves a secondary -L'-shaped lever 4| by reason of its engagement with a dovetailed slot 42 formed in the end of the horizontal portion of the secondary L-shaped lever 4|. The lever 4| is pivoted between a pair of depending arms 43 by means of a pivot pin 44 and the vertical portion of the secondary L- shaped lever 4| is bifurcated and carries a pivot pin 45. A link 46 is pivoted at one end to the pivot pin 45 and hence to the upper end of the vertical portion of the secondary L-shaped lever 4| and the other end of the link 46 is pivoted by 'a pin 41 to a pair of spaced arms 48 on a slide piece 49 which in turn is reciprocally mounted in 4 a body member 50 secured immediately beneath the bottom plate 25.

The bottom member 50 has an opening 5| therein centrally thereof and the slide piece 49 has an opening 52 therein in axial alignment .with the opening 5| and normally out of registry therewith. The slide piece 49 also has a depression 53 therein spaced inwardly thereof with respect to the opening 52 and adapted to register with the rounded lower end of a locking pin 54 which is positioned vertically beneath the exit tread plate 21 and secured thereto by suitable fasteners, as indicated by the numeral 55. It will thus be seen that at such time as a person steps upon the entrance tread plate 26, the previously described operation of the air valve takes place and causes the door to open. Simultaneously with the operation of the air valve and the downward movement of the tread plate 26, the bracket 33 moves downwardly and tilts the secondary L-shaped lever 4| causing it to move the lever 46 inwardly of the mechanism or to the left, as shown in Figures 3, 5 and 6 of the drawings. When this occurs the slide piece 49 moves inwardly or to the left as shown in Figures 3, 5 and 6 and brings the opening 52 into registry with the opening 5| beneath the locking pin 54. As the person actuating the device steps across the threshold area, the tread plate 21 is depressed by the weight of the person and the locking pin 54 moves downwardly into registry with the openings 52 and 5| in the slide piece 49 and body member 56, respectively, and prevents the slide piece 49 from returning to normal position, which action holds the link 46, the secondary L-shaped lever 4|, and the depending bracket 33 and thereby holds the entrance tread plate 26 in depressed position until such time as the person steps off the exit tread plate 21.

When this occurs, the springs 3| under the exit tread plate 2'! move the same upwardly and disengage the lockin pin 54 from the openings 52 and 5| in the slide piece 49 and the body member 5B, respectively, which releases the interconnecting means and permits the entrance tread plate It will thus be seen that the door is held open while the person passes therethrough and during such time as the person's weight is carried on the exit tread plate 21.

It will be obvious to those skilled in the art that it is desirable to protect persons who accidentally approach the door from the wrong side as they would otherwise be injured by the door opening against them if the mechanism were actuated. Such protection is afforded by forming a depression 53 in the slide piece 49 immediately beneath thelocking pin 54 when the slide piece 49 is in normal position in the body member 53. A person stepping on the exit tread plate 27 will cause the immediate engagement of the locking pin 54 in the depression 53 and thereby lock the slide piece 49 against movement with respect to the bottom 25 or the body member 50 in Whichit is positioned. Such action will hold the slide piece 49, the link 46, the secondary L-shaped lever 4| and the bracket 33 in stationary position and thereby hold the entrance tread plate 26 in elevated relation and thus prevent the operation of the air valve I8 and hence the opening of the door I I.

In this connection it will be observed that when there is no weight on the exit tread plate 21, the springs 3| normally hold the locking pin 54 out of engagement with the depression 53 and thereby render this automatic locking action inoperative except at such times as weight is placed on the exit tread plate 21 prior to or simultaneously with the placing of weight on the entrance tread plate 26.

By referring now to Figures 1 and 3 of the I drawings it will be seen that an envelope 55 is positioned about the entire actuator assembly including the bottom plate 25 and the tread plates 25 and H, respectively, and spanningthe transverse slot existing between the inner opposed edges of the tread plates 25 and 21. The envelope 56 is preferably provided with tapering nose sections 5'5 and 58 on the opposite ends and located adjacent the hinges 25 and 39, respectively, and is formed of flexible material such as rubber so that its elasticity permits the operation of the device enclosed therein and at the same time prevents the entrance of moisture or foreign materials which might interfere with the operation of the device. The tread plates 25 and 2] are preferably formed of cast aluminum properly ribbed to provide rigid structures.

It will thus be seen that the several objects of the invention are met by the device disclosed herein and that a simple and efficient actuator for door opening mechanisms has been disclosed which is usable with any of the conventional air piston and cylinder door operating mechanisms known in the art.

It will also be seen that the device operates the relatively remotely situated air valve by means of the interconnecting flexible cable 22 enclosed in the protective tubing 24. and it will occur to those skilled in the art that rods or suitable wire may be substituted for the flexible cable 22, if desired, without departing from the spirit of the invention,

Having thus described my invention, what I claim is:

An actuating device having a pair of tread plates positioned adjacent one another, each of which is independently and yieldingly supported, a device operatively connected with one of the said tread plates to enable downward motion thereof to be utilized in controlling a remotely located object and a locking device disposed beneath the said tread plates and connected with the other one of the said tread plates for temporarily supporting the first mentioned tread plate in elevated relation and rendering the said device inoperative when the last mentioned tread I plate is moved in advance of the first mentioned tread plate, the said locking device comprising -REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 169,549 Jacobsen Nov. 2, 1875 1,168,218 Merritt Jan. 11, 1916 1,205,464 Mack Nov. 21, 1916 1,216,345 Mirau Feb. 20, 1917 1,358,899 Tyler Nov. 16, 1920 1,589,353 Bock June 22, 1926 1,864,827 Jenkins June 28, 1932 1,985,653 Christie Dec. 25, 1934 

